ManyToManyField serialization in Django

Question

I walked through the following documentation at https://docs.djangoproject.com/en/2.1/topics/db/examples/many_to_many/ and tried to use it to learn serialization with DRF.

So, my models.py is:

class Publication(models.Model):
    title = models.CharField(max_length=30)

    class Meta:
        ordering = ('title',)

class Article(models.Model):
    headline = models.CharField(max_length=100)
    publications = models.ManyToManyField(Publication)

    class Meta:
        ordering = ('headline',)

My serializers.py looks like:

class PublicationSerializer(serializers.ModelSerializer):


    class Meta:
        model = Publication
        fields = ('title',)

class ArticleSerializer(serializers.ModelSerializer):

    publications = PublicationSerializer(read_only=True, many=True)

    class Meta:
        model = Article
        fields = ('headline', 'publications')

I created some objects via the shell:

>>> from publications.models import Article, Publication
>>> from publications.serializers import ArticleSerializer, PublicationSerializer
>>> p1 = Publication(title='The Python Journal')
>>> p1.save()
>>> p2 = Publication(title='Science News')
>>> p2.save()
>>> p3 = Publication(title='Science Weekly')
>>> p3.save()
>>> a1 = Article(headline='Django lets you build Web apps easily')
>>> a1.save()
>>> a1.publications.add(p1,p2,p3)
>>> serializer = ArticleSerializer(instance=a1)
>>> serializer.data
{'headline': 'Django lets you build Web apps easily', 'publications': [OrderedDict([('title', 'Science News')]), OrderedDict([('title', 'Science Weekly')]), OrderedDict([('title', 'The Python Journal')])]}

So, when I run the server everything is fine. This the JSON representation when I navigate to /articles:

[
    {
        "headline": "Django lets you build Web apps easily",
        "publications": [
            {
                "title": "Science News"
            },
            {
                "title": "Science Weekly"
            },
            {
                "title": "The Python Journal"
            }
        ]
    }
]

But in my urls.py, I have also a /publications link which shows me the list of publications:

[
    {
        "title": "Science News"
    },
    {
        "title": "Science Weekly"
    },
    {
        "title": "The Python Journal"
    }
]

So, the first JSON representation (/articles) shown above which shows me the articles gives me a list of publications related to the article. As I said before, this looks as expected. But in the 2nd JSON representation (/publications) which shows me the list of publications I can not see a list of articles related to each publication. How can I do that ? Should I add another ManyToManyField to Publication class ? Or is a ForeignKey field enough ? What I want is a JSON representation like the following when I navigate to /publications:

 [
        {
            "title": "Science News"
            "article":[                      <-- This info should be added
                         "..." , etc.
                      ]
        },
        {
            "title": "Science Weekly"
            "article":[ 
                         "..." , etc.
                      ]
        },
        {
            "title": "The Python Journal"
            "article":[ 
                         "..." , etc.
                      ]
        }
    ]

I hope somebody can help. Thanks in advance :)

Answer 1

You don't need to add any model fields. You just need to add "article_set" to the fields list in PublicationSerializer.